In those cases the system swaps entire skeletal meshes. So you wouldn’t want the hairline to be part of the body when you import the body. It would be a separate model imported separately from the body as it’s own file. Same for clothing, hair types, etc. That way the system can swap the hairline, hair type, clothing model on the character. If you import them as part of the body then the scripts can’t swap them but would have to swap the entire body because it would be a single asset. Ergo, import them separately, not as part of the body.
I separated the body model into parts using Maya but you actually don’t have to do that. I did it to simply show that the scripts can handle extremely modular character setups. For the Daz models what I would do if I were you would be to simply use the entire naked body as the Inherited Mesh. Meaning, don’t split it up into separate parts unless you know how to bake changes to all the morph targets in a 3d package. In fact, it’s probably recommended not to split up the base body because you’ll probably wind up with the seams being somewhat visible anywhere that you separate the mesh unless you know of some skin material magic that I don’t know of.
Then you would import the hairlines, hairs, clothing models, etc as separate models. So long as the hairline, leggings, shirts, etc all use the same skeleton you’ll be fine to set them as children of the Mesh (Inherited) as I did in Video 02. You’d just drag and drop ONE hairline, one clothing model, one hair type model onto the Mesh(Inherited) to add a new skeletal mesh as a child of the body in the Character Blueprint.
You can then set up an opacity mask in the skin material to make any part of the body under clothing transparent. Then swap that opacity mask based on what the character is wearing. In video 11 I show how to swap meshes using one of the templates. There’s a function, fairly simple one, in the Character Customizer system that I demo in video 11. It can be used to swap the hairline, swap the hair model, swap the clothing model, etc. It can swap any skeletal mesh so that it uses a different mesh. This would be how you’d change the clothing or hair type of your character.
When you change clothing you can also rework a template to not just change a clothing type but also change the opacity mask of the body model to hide the body under clothing. For the Genesis models this is fine since they aren’t that high of a poly count to begin with so it’s not like doing so would really waste any resources or at least it would be so minimal as to not warrant attention. You’d just be making part of the body invisible that’s under clothing.
Alternatively, if you’re good at rigging, you don’t even have to hide the body under clothing and so long as they are both using relatively the same skin they’ll move together. Effectively you’d treat it just like Daz3d software does in that case. Where you load the body in their program and then load up a clothing model and it moves with the character because it’s skinned the same as the body. The same concept can apply in UE4 using this system.
If you choose to go with the Opacity mask route and have issues setting up the slider/button to swap both the skeletal model and opacity mask just let me know. I’ve done it before.